Papers by Keyword: Electrochemical Finishing

Abstract: This paper is concerned with the problem of license plate recognition of vehicles. A recognition algorithm based on dynamic sliding window to binarize license plate characters is proposed. While a connected domain approach is presented to cope with the degradation characters. There are three steps to recognize the characters. First, the characters are classified by their features. Then, based on such classification a grid method is used to construct the feature vector. Finally, least square support vector machine is employed to recognize these characters. The test results show the high recognition rate and also illustrate the effectiveness of the proposed algorithm.

Abstract: The bar line is one of the important products of iron and steel industry, It is widely used in the construction of infrastructure facilities, construction and metal products industry. The programmable controller control system to replace the traditional relay control to control the hydraulic station, to complete the motor sequence control, and the pressure of the hydraulic oil contamination, temperature, automatic detection and alarm. Can satisfy the control requirements, reduce control cost, but also improves the control precision.

Abstract: A design system using a magnetic force with high efficiency to assist discharging dregs out of the electrode gap during the electrochemical finishing on the surface finish process that follows turning machining process is investigated in the current study. Through the equipment attachment, magnetic-assistance during electrochemical finishing can follow the turning process on the same machine. This process can be used for various turning operations. Among the factors affecting electrochemical finishing, the magnetic-assistance is primarily discussed. The experimental parameters are magnetic strength, distance between the two magnets, current rating, on/off period of pulsed current, feed rate of workpiece, and rotational speed of workpiece. A higher current rating with magnetic-assistance reduces the finishing time and avoids the difficulty of dreg discharge. Providing a large magnetic field intensity or using a small distance between the two magnets produces a larger magnetic force and discharge ability and better finishing. A large rotational speed of the workpiece and electrode produces better finishing. Pulsed direct current can slightly promote the effect of electrochemical finishing, but the current rating needs to be increased. The magnetic-assistance during the electrochemical finishing process makes a great contribution in a short time by making the surface of the workpiece smooth and bright.

Abstract: Electrochemical finishing with pulsed current (ECFP) is introduced in this paper. The main process parameters, such as electric parameter and inter-electrode gap, etc., were investigated. The results show that the ECFP is an effective finishing method for improving the machining quality as the result of the machining mechanism. The related experimental results show that the obtained surface quality and dimensional accuracy are improved significantly as the result of the application of the pulsed current. Moreover, machining quality is increased with shorter pulses.

Abstract: In processing of electrochemical finishing (ECF), electrochemical dissolution makes anodic surface micro-topography change. To identify the influence of the change on the distribution of electric-current field between electrodes, mathematical model describing the distribution of the electric-current field along the profile of the anodic surface micro-topography was established. The results of simulations and experiments show that the variation in the anodic surface micro-topography makes the distribution density of the electric-current uniform, and the sharp or peak-like micro-topography is in favour of improving the finishing ability of ECF.

Abstract: The current study discusses the surface finish of several common die materials, of which the screw-surface is finished by compound processes of electrochemical finishing and burnishing. The burnishing-tool uses ceramic material connected with the electrode and moves, following the electrode, to burnish the workpiece. In the experiment, the electrode is used with a continuous and pulsed direct current. The results show that the use of a higher rotational speed for the electrode and burnishing-tool is advantageous to the finish. A partial form with a thinner heavy section performs the best finish effect in the current investigation. Pulsed direct current can slightly improve the finish effect. The burnishing process can increase the finish effect. An effective and low-cost finish processes through burnishing assistance following electrochemical finishing after screw machining offers a fast improvement for the surface roughness of the screw-surface and is a new application in the screw finishing process.

Abstract: Electrochemical finishing (ECF), which is based on anodic electrochemical dissolution (ECD) process, appears to be very promising as a future finishing technique, since in many areas of applications it offers attractive advantages over traditional finishing processes such as its applicability regardless of material hardness, no cathode tool wear, smooth and bright surface, and a wide range of materials that can be finished. Therefore, in this contribution, a review is presented on current research, advancement and industrial practice in ECF. This paper highlights the influence of various predominant factors of ECF, including power supply, design and advancement of cathode tool, etc. The finishing mechanism of ECF and its hybrid processes are also concerned in this paper.

Abstract: Gears’ surface quality and modification characteristic have an important influence on its working performance. Pulse Electrochemical Finishing (PECF) could get excellent surface topography. In this project, PECF with a scanning cathode is used to finishing the cylinder gear. Tooth profile modification is realized by PECF with an uneven interelectrode gap distribution along the tooth profile and tooth lead modification is realized by PECF with a variable moving velocity of the cathode. The experimental results show that the tooth surface roughness could be decreased from Ra 3.9μm to Ra 0.35μm, which means that the PECF process possesses the finishing ability for the raw surface tooth, and the difference of material removal of PECF with an uneven interelectrode gap distribution could be 46μm and the material removal could be controlled by regulating the moving velocity of the cathode, which means tooth profile and lead modification could be realized by PECF.

Abstract: This paper studies the performance assessment of magnetic-assistance electrochemical finishing using an effective design system and magnetic force to the electrolyte to assist the dregs discharge on zinc alloy beyond die casting by electrochemical finishing as a finish process on the freeform surface of castings. An outer shell of toy vehicle is taken for instance in the experiment. A small distance between the two magnets or large magnetic field intensity provides larger magnetic force and discharge ability. A higher current rating with magnetic-assistance can avoid the difficulty of dreg discharge, thus reducing the finish time. Pulsed direct current can slightly promote the finishing effect, but the machining time is increased. Thus the magnetic-assistance electrochemical finishing without pulsed current is recommended for the finish process. It is a great contribution that the magnetic-assistance electrochemical finishing just needs quite short to make the freeform surface of workpiece smooth and bright.

Abstract: A new finishing method of holes that uses an effective electrode and a nonconductive roller to execute the design of synchronous processes of ultrasonic electrochemical finishing and rolling-leveling is investigated. The submitted processes can be used among the traditional techniques of various holes machining. Through simple equipment attachment, ultrasonic electrochemical finishing and rolling-leveling can follow to execute the finishing process on the same machine. Among the factors affecting finishing processes, the performance of rolling-leveling combined with ultrasonic electrochemical finishing is primarily discussed. In the experiment, the electrode is used with continuous and pulsed direct current. The controlled factors include roller material, roller geometry, chemical composition and concentration of the electrolyte, and flow rate of electrolytes. The experimental parameters are frequency and power level of ultrasonics, feed rate of electrode and roller, rotational speed of the finish-tool, die material, electrical current rating, and pulsed period. The design of the synchronous processes through rolling-leveling is the most influential parameter in this study. An adequate finish-tool rotational speed produces better finishing. The average effect of the ultrasonic is better than the pulsed current while the machining time needs not to be prolonged by the off-time. An effective and low-cost finishing process through the ultrasonic electrochemical finishing and using the rolling-leveling assistance after the process of traditional holes machining make the surface of the holes smooth and bright is presented.